This may have introduced bias, through issues of social desirability.
The observational nature of this study may also have introduced variability through diagnostic and microbiology practice.
Likewise, the days, language and times of the day in which the street survey was conducted may also have introduced bias, through not targeting those at work, and possibly those with a higher education level, who may be more informed about the healthcare services available at the end-of-life and who speak English.
This may have introduced "expectation" bias through greater effort being made to identify neoplastic disease at colonoscopy after a positive result and might potentially have increased the specificity of faecal haemoglobin.
Other studies have investigated the sit-to-stand activity as one element of an exercise program in community-based settings [ 48- 50] or have introduced an exercise through the use of additional therapists or research assistants.
As of January 2014, 53 countries have introduced rotavirus vaccines through their national immunization programs, including 20 low-income countries eligible for vaccine introduction support from Gavi, the Vaccine Alliance (formerly the Global Alliance for Vaccines and Immunizations) [ 14].
Several groups, including the Black Eyed Peas, R.E.M. and Nine Inch Nails, have introduced their latest releases through MySpace.
Limiting recruits to 5 12 per centre may have introduced some selection bias through under-representation of less common presentations of spasticity.
Recognised limitations: Limiting recruits to 5 12 per centre may have introduced some selection bias through under-representation of less common presentations of spasticity.
The standards of conduct we have introduced require suppliers to go through a culture change in the way they treat consumers.
